Improvement in steam-generators



dettati gisten @wat @imite JOSEPH A. MILLEa'oF NEW vonk, N. Y.

Letters Patent No. 106,388, dated August 16, 187D.

IMPROVEMENT IN STEAM-GENERATRS.

The Schedule referred t in these Letters Patent aud-making part ofthesame.-

inthe art to make and use the same, reference being had totheaccompanying drawing forming part of this specification, iu which-Figure 1 represents a sectional perspective view of my improved tubulousboiler.

Figure 2 is averticaltransverse section of the same, the plane ofsection being indicated by the line a: z, fig-1.

Figure 3 is adetail transverse section on an cn` larged scale of one ofthe tubes.

Figure 4 is a detail longitudinal section of the same.

Figure 5 is aV detail transverse section of some tubes showing themanner of erecting the bridge-wall between the saine.

Similar lett-ers ot' reference indicate corresponding parts. v

This invention relates tp tubular steam-boilers, and the principalobject aimed at -is to impart a progressive heat to the water and steam,the maximum of temperature being at the water-outlet, and the minimum atthe water'inlet ot pipes A.

The invention consists in the Vcombination of means employedrfor theaccomplislnnent of this purpose, and which will be described andspecified.hereinafter.4

In the drawing- The letter A represent-s aseries of inclined pipesparallel to each other. Their front ends are open, andare fast in the.wall a, while their rear ends are closed by the caps C.

These caps have projections 7)by which thcymay be. unscrewed with awrench, and are alsov formed of a diameter suitable to the intendeddistance between the tubes. They are made to rest upon one another.

B is a steam-box, to .which the front ends of the steam-tubes areattached, and is inclined ina degree to correspond with the inclinationof those tubes.

D is a bridge, which supports the lowest 4row of pipes and forms one ofthe walls ot' the furnace.

E represents a series of small tubes placed within the'tube's A, butextending beyond them in front, and fastened to a pla-te of the box B.

They have at their lower ends lips d, by which they are held parallel tothe circumjaccnt tubes.

`Each 'internal tube -is preferably formed of about one-halt' thediameter` of the one surrounding it.

The .lips d are made to slide in the tubes A by means of the slots e.

The tubes E are open at both ends, and do not extend in the rear to thebottom of the surrounding A tubes.

Gr are tire-bricks or blocks 4of any suitable material, shaped to fillthe spaces between the tubes A.

K represents the `fire-space, which is located beneath the upper halt`of the tnbesfso as to produce the greatest intensity ofheat at thesteam-outlets, and the least at the lowest points where the water issuesfrom the tubes E.

'B' is the water-chamber, which directly supplies the pipes E and E',the chamber into which the steam issues from the tubes A.

B" is the dome, from which the steam passes into' the discharge-pi pe H.

The mode of operation is as follows:

The water 4naturally passes through the pipes E by its own gravity, andseeks their depressed ends, where it is emptied into the. lower ends oftubes A.. At

vthisr-point is -the minimum of temperattue,` by

'reason of its greater distance from the lire. As it ascvnds, theintensity of the heat progressively increases until it is converted intosteam, and tends to ascend by reason of its own levity. 'As the `steamthen proceeds toward the outlet of the tube, it becomes morel and moresuperheated, until it finds its way `to the dome. K

I am awarel that tubes A E, one within another, steam-box B, andthere-space K, aree-ach, in themselves, old.

ThatA therefore, I esteem to be of my invention, and desire to protectby Letters Patent, is-

The two series of inclined pipes A E, one within the other, combinedwith a re-space Kunder the upper portion 'of said pipes, all arranged tosubject the water and steam to progressive augmentations ot' heat, asset forth. l

JOSEPH A. MILLER.

Witnesses:

WM. A. KIMBALL, J. A. GRosvENou.

